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<div class="titlepage"><div><div><h3 class="title">
<a name="phoenix.starter_kit.arguments"></a><a class="link" href="arguments.html" title="Arguments">Arguments</a>
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<p>
        Arguments are also functions? You bet!
      </p>
<p>
        Until now, we have been dealing with expressions returning a nullary function.
        Arguments, on the other hand, evaluate to an N-ary function. An argument
        represents the Nth argument. There are a few predefined arguments arg1, arg2,
        arg3, arg4 and so on (and it's <a href="http://www.boost.org/libs/lambda/doc/index.html" target="_top">BLL</a>
        counterparts: _1, _2, _3, _4 and so on). Examples:
      </p>
<pre class="programlisting"><span class="identifier">arg1</span> <span class="comment">// one-or-more argument function that returns its first argument</span>
<span class="identifier">arg2</span> <span class="comment">// two-or-more argument function that returns its second argument</span>
<span class="identifier">arg3</span> <span class="comment">// three-or-more argument function that returns its third argument</span>
</pre>
<p>
        <code class="computeroutput"><span class="identifier">argN</span></code> returns the Nth argument.
        Examples:
      </p>
<pre class="programlisting"><span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">3</span><span class="special">;</span>
<span class="keyword">char</span> <span class="keyword">const</span><span class="special">*</span> <span class="identifier">s</span> <span class="special">=</span> <span class="string">"Hello World"</span><span class="special">;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">arg1</span><span class="special">(</span><span class="identifier">i</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>        <span class="comment">// prints 3</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="identifier">arg2</span><span class="special">(</span><span class="identifier">i</span><span class="special">,</span> <span class="identifier">s</span><span class="special">)</span> <span class="special">&lt;&lt;</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">endl</span><span class="special">;</span>     <span class="comment">// prints "Hello World"</span>
</pre>
<p>
        (See <a href="../../../../example/arguments.cpp" target="_top">arguments.cpp</a>)
      </p>
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        Learn more about arguments <a class="link" href="../modules/core/arguments.html" title="Arguments">here.</a>
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